This invention relates to a knitting needle for use with a hand-operated knitting apparatus for domestic use, and more particularly to a knitting needle suitable for knitting with a relatively heavy yarn.
Knitted garments such as, for example, a pullover, vest, cardigan and so on, are knitted favorably with heavy or relatively bulky yarns such as three- or four-ply yarns. Such garments are conveniently knitted on specific knitting apparatus generally called bulky or heavy yarn knitters which are available on the market. Conventional heavy yarn knitters, especially hand-operated knitters for domestic use, have knitting needles, the pitches of which are generally selected to be between 8 and 10 mm, while the needle pitch of conventional home knitters suitable for knitting with a medium size yarn is normally 4.5 mm. Obviously, as the needle pitch increases, the needle bed must have a greater length in order to accommodate the same predetermined number of knitting needles therein, resulting in a substantial increase of the weight of the entire needle bed and hence the machine.
If the needle pitch could be decreased, for example, to 6 mm, this disadvantage could be improved mitigated to some degree. But a mere reduction of the needle pitch will cause another problem: it results in a corresponding increase of the number of knitting needles which are at a time engaged with and operated by a knitting cam on the machine carriage to knit a yarn into stitches, and such an increase will make the operation of the carriage correspondingly heavier, since those knitting needles act to draw or pull a yarn supplied thereto in opposite directions relative to each other, the yarn extending in a zig zag configuration among those needles and adjacent sinker elements of the machine. Thus, in view of the cooperation between a yarn and knitting needles, the knitting cam on the carriage may preferably have a steeper inclination relative to the direction of movement of the carriage on the needle bed in order to decrease the needles which are operated at a time by the knitting cam. On the other hand, the steeper the inclination of a cam, the greater the friction thereby, as well known to those skilled in the art. Accordingly, an optimum inclination of the knitting cam will be determined by a compromise or function between the friction between the number of knitting needles which are operated at a time by the knitting cam and the friction between the knitting cam and such knitting needles.
Conventional medium size yarn knitters as mentioned above have their knitting cams disposed normally at an angle between or for movement to present an angle between 45 to 50 degrees, as an optimum value, relative to the carriage moving direction. In heavy yarn knitters on which a heavy yarn is used for knitting which provides a greater frictional resistance against the knitting needles, the knitting cams could obviously be disposed at a significantly steeper angle relative to the carriage moving direction.
Recent hand-operated home knitters progressively employ plastic materials for their machine components; even knitting cams on a machine carriage are sometimes made of a suitable synthetic resin material such as, for example, polyacetal or ABS, in order to reduce the weight of the machine and production of noises caused by collisions of such cams with butts of knitting needles. On the contrary, knitting needles are normally made of steel material. Thus, if the carriage is operated so rapidly or strongly on the needle bed that its knitting cam is forcibly collided or pressed by butts of knitting needles, the plastics cam may possibly be damaged by the steel needle butts, and once a scar or mark is formed on the cam, it will provide a greater resistance to needle butts so that the cam will be further damaged thereby, which may cause a trouble in knitting and in the machine. The disposition of knitting cams in a steeper inclination relative to the carriage moving direction will present a corresponding increase of such harmful collisions of knitting cams by needle butts.